Nachhaltigkeit

TerraNova Energy

Sustainablity

Worldwide our society needs far-reaching and new solutions for more climate protection and resource conservation. We are making valuable contributions to this with our technologies. For us, this challenge is the greatest motivation. Every day. One hundred percent. Our solutions are innovative, efficient and economical. They improve the ecological footprint of our customers’ projects by utilizing organic waste streams. This is the only way to implement pioneering innovations and ensure our ultimate goal: To help you successfully implement your environmental projects in a sustainable manner.

Wirtschaftlichkeit Terra Nova Energy

Profitability

Reduction of waste, substitution of fossil energy sources, avoidance of CO2 emissions, independence from import of fertilizers

Kreislaufwirtschaft - Terra Nova Energy

Circular economy

Upgrading of organic waste, recovery of Phosphorous

Umwelt - Klimaschutz - Umwelt- Klimaschutz

Environmental and climate protection

Reduction of pollutants and emissions, avoidance of waste streams, renewable energy

Profitability

The profitability of environmental projects will be improved by the implementation of the TerraNova® technologies through:

Reduction of waste

Biowaste and sewage sludge are usually disposed of with a high water content of up to 80%. This requires considerable transport effort and, if incinerated for safe disposal, a high energy input.

TerraNova®ultra reduces, for example, 1000 kg of dewatered sewage sludge, as it is produced in most sewage treatment plants, to only about 250 kg of residual material. On the one hand, this is achieved by energy-saving separation of the sewage sludge water; on the other hand, carbon and nitrogen in the sewage sludge are also broken down and separated in an exothermic reaction during the process, so that the residual quantity and thus the disposal costs for the sewage treatment plants are significantly reduced.

Depending on the amount of sewage sludge and the size of the plant, the full costs ( = operating costs + capital costs of the investment) of the TerraNova®ultra process per ton of sewage sludge are 25-50 EUR. For example, if a wastewater treatment plant produces 15,000 tons of dewatered sewage sludge per year, which is disposed of today for 70 EUR per ton, the use of TerraNova®ultra will save about 300,000 EUR in costs per year. Since increasing disposal costs for sewage sludge must be expected due to stricter environmental regulations, the profitability of such projects will even increase in the future.

Production of a renewable fuel to replace fossil coal

TerraNova® coal is renewable because it is produced from waste materials that are regenerative. Thus, when burned, only the amount of CO2 that was removed from the atmosphere during the growth of the biomass is released. This is a significant advantage over fossil coal, which releases CO2 that has been captured for thousands of years, increasing the concentration of greenhouse gases in the atmosphere.

Thus, when TerraNova® coal is burned, the user not only saves the cost of fossil coal or other fuels, but also does not have to pay additional taxes for the resulting CO2 emissions, which are required in many countries.

Replacement of biological stabilization processes

These processes include anaerobic or aerobic treatment stages, the aim of which is, on the one hand, to reduce the biological activity of the residual substances and, on the other, to break down organic matter. Since this is a biological process, long treatment times are necessary for this purpose, requiring correspondingly large treatment plants. In addition, the desired degradation of organics is not effective – often only about half of it is degraded, since the bacteria convert only the easily usable fraction within the treatment time. As a result, there is still a residual material that has to be disposed of.

The TerraNova® systems, on the other hand, convert almost all of the organic matter and stabilize it in the form of TerraNova® coal. Thus, a much higher conversion efficiency is achieved and no residual material remains. In addition, the plants are smaller in size and require less installation space. The cost analysis using sewage sludge as an example demonstrates that the TerraNova® process has lower total costs than plants for anaerobic sludge digestion, even for smaller sewage treatment plants.

Full costs

Increase in biogas yield

Biogas plants achieve significant yield increases by integrating a TerraNova® system. TerraNova®lysis is used to thermally break down the input materials, making the organic material more easily degradable for the biogas bacteria in the subsequent process. In simple terms, it is “cooked” for better digestion.

This facilitates the conversion processes and increases the yield of bio-methane by 25-35% when digesting sewage sludge (mixture of primary sludge and activated sludge). Furthermore, smaller digesters can be used as the residence time can be reduced.

If, in addition, the remaining digested sludge is further processed in a downstream TerraNova®ultra plant and the water separated in the process is returned to the digester, the bio-methane yield is increased by a further 15%, since the water contains large amounts of easily degradable carbon.

This boosts the overall bio-methane yield by up to 50% compared to the current state of the art, and significantly improves economic viability and conversion efficiency.

Phosphorus recovery

The recovery of phosphorus from residual materials is politically desired and necessary, as natural resources are depleted. In some countries, the obligation to recover phosphorus, e.g. from sewage sludge, has already been incorporated into law.

Nevertheless, phosphorus recovery is not economically feasible with any of the processes available today. Depending on the process, costs range from EUR 2.50 to EUR 15 per kg of phosphorus (P). In addition, recovery usually requires pre-treatment of the sewage sludge in mono-incineration plants to be built specifically for this purpose, which further increases the overall costs.

The TerraNova® process can be carried out without pre-treatment of the sewage sludge in a mono-incineration plant, directly at the site of the wastewater treatment plant. The costs are comparatively low at EUR 3.00 to EUR 4.00 per kg phosphorus (P).

Circular economy: Upgrading organic waste, recovery of valuable materials

TerraNova® technologies enable the implementation of a local circular economy for your organic waste materials. These are safely sterilized at a temperature of 180-200°C, broken down into their components in a series of chemical reactions, and then converted into a type of “biocoal” in TerraNova®ultra systems.

At TerraNova® process temperatures, a number of organic contaminants, such as drug residues, are reduced or eliminated. Dioxins and furans cannot be produced in the TerraNova® process due to the reaction conditions – this is an important advantage over pyrolysis processes for producing biochar. In addition, the conversion efficiency is higher, as in pyrolysis processes a large part of the carbon is lost during the production of the biochar.

In addition to TerraNova® coal, phosphorus can also be recovered in the process. Phosphorus is extracted from phosphate rock, with reserves concentrated in just a few countries around the world. Europe, for example, is completely dependent on phosphorus imports to produce fertilizers for agriculture. In some countries, therefore, a legal obligation to recover phosphorus has already been established.

The TerraNova® phosphorus recovery process enables direct recovery from sewage sludge without the need for prior drying and incineration. It thus significantly simplifies the process chain and saves investments and costs. In addition, due to the mild process conditions, the TerraNova® phosphorus fertilizer is easily available to plants and achieves the highest fertilizing effect compared to other processes.

Experiment results
With a recovery rate of 60-80%, the patented TerraNova® process is the most effective process for direct recovery from sewage sludge. This is enabled by the uniquely high dewatering performance in the separation of the phosphorus.

The TerraNova® phosphorus fertilizer is approved as calcium phosphate according to the German Fertilizer Regulation 1.2.9 Table 6.2.4 and complies with the requirements of the European Fertilizer Regulation 2019/1009 for the product group CMC12.

Environment and climate protection

Climate-friendly sewage sludge disposal

The energy- and CO2-balance of sewage sludge disposal is significantly improved by using the TerraNova®ultra process, since less water has to be transported and evaporated in an energy-intensive way, more biogas can be produced and transportation is reduced.

According to an independent study by the Kompetenzzentrum Wasser Berlin1 , the energy surplus that can be generated can be almost doubled if the TerraNova®ultra process is integrated into the sewage sludge treatment process between the dewatering of the sewage sludge to its incineration.

In addition, for each ton (calculated in dry matter) of sewage sludge treated by the TerraNova®ultra process, 0.5 tons of CO2 emissions are saved. In the case of a wastewater treatment plant for 100,000 inhabitants, this corresponds to around 600 t less greenhouse gas emissions per year.

Improving the energy efficiency of sewage sludge incineration plants

Sewage sludge incineration plants have been built using the same basic principle for more than 50 years. To allow the water-containing sewage sludge to be combustible, the heat generated during incineration must be used to pre-dry the sewage sludge and evaporate the sludge water. This is a very energy-intensive pretreatment step that consumes most of the energy generated. In some more modern plants, the remaining residual heat is used to generate electricity. However, the overall efficiency is very poor at <10% of the fuel input and often just covers the plant’s own energy demand.

In contrast, TerraNova®ultra separates the water contained in the sewage sludge in a very energy-efficient manner. Correspondingly more regenerative energy can be generated in the incineration plant either in the form of waste heat in a connected heating network or converted into electricity – and this can even be flexibly adapted to demand. The effect is significant:

If only about 1/4 of the sewage sludge volume in an incineration plant is pretreated by TerraNova®ultra, 50% more electrical energy can be generated in winter than with conventional sewage sludge incineration plants. In summer, when the heat output to the heating network is reduced, the TerraNova®ultra process can be used to flexibly adjust the operation mode and even generate 100% more regenerative electrical energy.

HTC – Eine energetische Betrachtung für Projekte zur Klärschlammmonoverbrennung

Sewage sludge drying with minimum energy input

Conventional sewage sludge drying plants separate the water contained in the sludge by evaporation. Since overcoming the aggregate state of liquid to vapor is very energy-intensive and the energy required for this can only be partially recovered in downstream plant sections as condensation heat, even modern dryers today require between 800 kWh and 1000 kWh of thermal energy per ton of water separated. In addition, large quantities of air have to be moved, which also results in high electrical energy requirements in the range of over 100 kWh per ton of separated water.

In the TerraNova®ultra process, on the other hand, almost all the water contained in the sewage sludge is separated mechanically. This is comparable to squeezing out a wet sponge instead of drying it with a hair dryer. Only a small amount of thermal energy is required for pretreating the sewage sludge in the TerraNova®ultra process to enable efficient “squeezing”. As a result, the energy requirement of the TerraNova®ultra process is up to 80% lower than that of conventional sewage sludge drying processes, amounting to 130 kWh of thermal energy and 18 kWh of electrical energy per ton of dewatered sewage sludge.

Waste heat at elevated temperatures, e.g. the exhaust gas stream from gas engines, can be used as a heat source for the TerraNova®ultra process, which can be found in cogeneration plants to generate electricity from biogas.

Increasing the biogas yield

We offer two solutions to increase the efficiency of biogas plants:

TerraNova®lysis performs a novel, intensive thermal hydrolysis of the input material. In this process, the material is pre-treated at temperatures of 160-170°C over a particularly long period of several hours to enable more effective anaerobic conversion into biogas by the bacteria in the subsequent digestion process. This results in an increase in biomethane potential (BMP) of about 35% for sewage sludge, for example – one of the highest values compared to other processes.

In addition to the long treatment time, the special feature of TerraNova®lysis is its ability to process even material with a very high dry matter content of up to 30%. This allows small, compact plants. The energy consumption of the process is very low due to the integrated heat recovery, the high concentration of the material to be treated, and the absence of steam as a heat carrier, and amounts to only 110 kWh of heat and 16 kWh of electrical energy per ton of input.

The TerraNova®ultra process is used to upgrade the digestate into a biochar, which is then put to further use. The process water separated in the TerraNova®ultra process contains a high proportion of easily degradable carbon, which is returned to the biogas process and additionally increases the biogas yield.

The patented combination of TerraNova®lysis and TerraNova®ultra thus results in an increase in biogas yield of approx. 50% and the production of a further usable product in the form of biocoal.

Avoidance of truck transports

Sewage sludge is normally disposed of by truck. Since the local utilization of sewage sludge on agricultural land is becoming increasingly restricted due to higher environmental standards, longer disposal routes to central incineration plants are often necessary.

Unfortunately, these transports are also often associated with empty runs on the way back, so that, for example, for a city with 100,000 inhabitants to dispose of sewage sludge to an incineration plant 50 km away, approximately 24,000 truck kilometers are required annually. If there is no sludge digestion at the sewage treatment plant site, this value even increases to almost 40,000 truck kilometers.

By pretreating the sewage sludge in the TerraNova®ultra process at the site of the wastewater treatment plant, the residual quantity to be disposed of is reduced to about 1/4. This is achieved by the mechanical removal of the contained sludge water and by the decomposition and separation of carbon and nitrogen during the exothermic reaction of the TerraNova®ultra process.

This saves about 18,000 and 30,000 truck kilometers per year, respectively – an important contribution to relieving road traffic.

Avoiding pollutants in soils and groundwater

Manure, digestates and sewage sludge are widely used today for fertilization in agriculture. However, their use is not without controversy, since in addition to the recycling of nutrients, pollutants such as pharmaceutical residues, heavy metals, germs, viruses, bacteria and organic pollutants are also introduced into the soil.

TerraNova®ultra can significantly reduce this pollutant discharge as needed, depending on the application:

If the heavy metal load in the soil is to be minimized, the organic residues are pre-treated in the TerraNova®ultra process, the TerraNova® carbon is separated in the process and used for energy in an incineration. The remaining process water contains a large share of the nutrients, is sterilized and low in heavy metals. It can be used as an organic liquid fertilizer.

If groundwater contamination by nutrients, especially nitrogen, is to be prevented, the use of TerraNova® coal for fertilization is advantageous: for example, the leaching of nitrate is lower by a factor of 4 and of ammonium nitrogen by as much as a factor of 60 compared with untreated residual materials.2

Potassium, phosphorus and micronutrients are also better bound in the TerraNova® coal for effective fertilization, while at the same time the cation exchange capacity is improved by a factor of 3 to improve uptake by the plant.

The positive fertilization effect of TerraNova® Charcoal was demonstrated in a 3-year field trial conducted by the Humboldt University of Berlin.3

Multi-resistant germs, which are increasingly also found in intensive livestock farming and are exposed to the environment via manure fertilization, are classified by the World Health Organization as one of the greatest future threats. The process conditions of TerraNova®ultra reliably destroy these down to the DNA level.4 As a result, safe recycling of livestock manure will continue to be possible in the future.

Avoiding the emission of greenhouse gases

When organic waste materials are applied to soils or disposed of in landfills, the carbon compounds decompose over time into CO2, which escapes into the atmosphere. Furthermore, insufficient oxygen supply during the decomposition process can also produce methane (CH4) and, in the case of excess nitrogen, nitrous oxide (N2O). Methane is more harmful to the climate than CO2 by a factor of 25 and nitrous oxide by a factor of 300.

These emissions are completely avoided when organic waste materials are recycled in TerraNova®ultra – in the process itself, only about 2% of the carbon contained in the input material is released into the atmosphere in the form of CO2 through the exothermic reaction. The rest is put to utilization.

The situation is similar for sewage sludge mono-incineration plants: since these have to be operated at comparatively low temperatures around 900°C due to the threat of slagging of the sewage sludge in the incineration process, nitrous oxide is emitted with the combustion gases. This can be remedied by a complex post-combustion process, which, however, requires the use of fossil fuels.

Alternatively, mono-combustion can be omitted and, by using the TerraNova®ultra process instead, the resulting sewage sludge coal can be used in cement plants: its process temperatures of around 1,500°C reliably prevent the formation of nitrous oxide.

Recovery of a low-pollutant phosphorus fertilizer

Global reserves of raw phosphate are running out – availability is only assured for a few decades and is also limited to a few regions in the world. The European Union, for example, is completely dependent on the import of phosphorus as fertilizer for agriculture. With the ever-growing world population, this poses an existential problem, since phosphorus is indispensable as an element for life of all kinds and cannot be replaced by any alternative. To date, however, large quantities of phosphorus have been irrevocably lost through washouts of fertilizers into rivers and oceans or through the incineration of waste containing phosphorus. In addition, the remaining reserves are increasingly contaminated with cadmium and uranium – in some cases, limits for fertilizers are already being exceeded today.

Sewage sludge offers great potential for the future recovery of phosphorus. In recent years, numerous recovery processes have been developed, most of which however require the sewage sludge to be incinerated in dedicated mono-incineration plants.

The TerraNova® process offers a simpler alternative to this: the phosphorus is recovered directly from the dewatered sewage sludge, without transport and pre-treatment in centralized mono-incineration plants. It thus significantly simplifies the process chain and saves investments and costs. In addition, due to the mild process conditions, the TerraNova® phosphorus fertilizer is easily available to plants, is low in pollutants and achieves the highest fertilizing effect compared to other processes.

Experiment results

With a recovery rate of approx. 60-70%, the patented TerraNova® process is the most effective process for direct recovery from sewage sludge. This is made possible by the uniquely high dewatering performance during the separation of the phosphorus.

The TerraNova® phosphorus fertilizer is approved as calcium phosphate according to the German Fertilizer Regulation 1.2.9 Table 6.2.4 and complies with the requirements of the European Fertilizer Regulation 2019/1009 for the product group CMC12

Quellenangaben
1 Remy et al.: “Hydrothermale Carbonisierung: eine neue Option der Klärschlammbehandlung”, Korrespondenz Abwassser, Abfall 2015 (62) Nr.4
2 Ro, K.S., et al. Leachate water quality of soils amended with different swine manure-based amendments. Chemosphere (2015), http://dx.doi.org/10.1016/j.chemosphere.2015.05.023
3 Carbiophos Projekt 2016
4 Ducey et al. HTC treatment of livestock mortality for pathogen and DNA reduction, Front. Environ. Sci. Eng. 2017, 11(3): DOI 10.1007/s11783-017-0930-x

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